A police officer will spend time behind bars after being accused of using a metal detector to find rare gold coins and stealing them, according to police in the United Kingdom.

Now, the former Norfolk Police officer who found the rare gold coins on a farmer's land while metal detecting, was sentenced at the Ipswich Crown Court to 16 months in prison.

The theft was also described as "a serious heritage crime" by prosecutors.

According to the police investigation, 50-year-old David Cockle had permission from a Norfolk landowner to use a metal detector with an agreement that anything he found he would report and surrender.

He found 10 Merovingian Tremissis gold coins from Gaul (France), dating back to the sixth or seventh centuries. Such finds are extremely rare in this country and to find them was a significant discovery.

A similar find in the same location by a different person was reported and declared treasure trove.

Instead of notifying the landowner and the proper authorities, Cockle sold the coins to a dealer for 15,000 pounds ($18,222), and kept the money for himself.

This was a serious breach of trust by a police officer and in doing this, he was not only stealing the coins, he was committing a serious heritage crime.

Thankfully in this case, eight out of the 10 coins were later recovered by the police. Cockle will be banned from engaging in metal detecting activity for five years.

If he is found violating the ban, he could face a sentence of up to five years in prison.